Testosterone in the womb governs your sexual orientation

“Conclusion
At least for females, found differences in 2D:4D within pairs of identical twins with discordant sexual orientations empha- size the potential relevance of prenatal androgen exposure in the development of sexual orientation, and this independent of one’s genetic makeup. Additional work using other indices of prenatal androgen exposure, including measurement of testosterone levels in amniotic fluid (Auyeung et al., 2009), ano-genital distance (Pasterski et al., 2015), and oto-acoustic emissions (Rahman, 2005), could provide further insight into the development of discordant sexual orientations in geneti- cally identical individuals.”

Archives of Sexual Behavior https://doi.org/10.1007/s10508-018-1262-z
ORIGINAL PAPER
Finger Length Ratios of Identical Twins with Discordant Sexual Orientations
Tuesday M. Watts1 · Luke Holmes1 · Jamie Raines1 · Sheina Orbell1 · Gerulf Rieger1
Received: 8 December 2017 / Revised: 17 April 2018 / Accepted: 19 June 2018 © Springer Science+Business Media, LLC, part of Springer Nature 2018